<template>
    <div>
  <span
          :sendSync="sendSync"
          :autoStart="autoStart"
          :defaultVal="defaultVal"
  >{{countString}}</span>
    </div>
</template>

<script>
    export default {
        name: 'timer',
        data() {
            return {
                isStart: false,
                globalTimer: null,//获取setInterval对象值
                countString: '0秒', //用来显示时间
                day: 0,
                hour: 0,
                minute: 0,
                second: 0,
                millisecond: 0,
                countVal: this.defaultVal, //获取初始值
                pauseTime: 0,
            }
        },
        watch: {
            'countString': {
                deep: true,
                handler: function(val, oldVal) {
                    var vm = this
                    if (vm.needSendSunc) {
                        vm.passToParent(val)
                    }
                }
            },
            'needSendSunc': {
                deep: true,
                handler: function(val) {
                    var vm = this
                    if (val) {
                        vm.passToParent(vm.countString)
                    }
                }
            }
        },
        props: {
            sendSync: {
                type: Boolean,
                default: false,
            },
            autoStart: {
                type: Boolean,
                default: false,
            },
            defaultVal: {
                type: Number,
                default: 0,
            }
        },
        mounted() {
            var vm = this
            if (vm.autoStart) {
                vm.startCountFn()
            }
        },
        computed: {
            needSendSunc: function() {
                return this.sendSync
            }
        },
        created: function() {
            this.$on('startCount', function() {
                this.startCountFn()
            });
            this.$on('stopCount', function() {
                this.stopCountFn()
            });
        },
        components: {},
        methods: {
            counterFn: function(counterTime) {
                var vm = this
                var nowDate = new Date().getTime()
                if(vm.pauseTime == 0){
                    var num = nowDate - counterTime //计算时间毫秒差
                }else{
                    vm.pauseTime = vm.pauseTime +10
                    var num = vm.pauseTime - counterTime //计算时间毫秒差
                }
                var leave1 = num % (24 * 3600 * 1000)  //计算天数后剩余的毫秒数
                var leave2 = leave1 % (3600 * 1000)    //计算小时数后剩余的毫秒数
                var leave3 = leave2 % (60 * 1000)   //计算分钟数后剩余的毫秒数
                vm.day = Math.floor(num / (24 * 3600 * 1000)) //计算相差天数
                vm.hour = Math.floor(leave1 / (3600 * 1000))//计算相差小时
                vm.minute = Math.floor(leave2 / (60 * 1000))//计算相差分钟
                vm.second = Math.round(leave3 / 1000) //计算相差秒
                if (vm.day > 0) {
                    vm.countString = `${vm.day}天 ${vm.hour}小时 ${vm.minute}分 ${vm.second}秒`;
                } else if (vm.hour > 0) {
                    vm.countString = `${vm.hour}小时 ${vm.minute}分 ${vm.second}秒`;
                } else if (vm.minute > 0) {
                    vm.countString = `${vm.minute}分 ${vm.second}秒`;
                } else {
                    vm.countString = `${vm.second}秒`;
                }
            },
            startCountFn: function() {
                var vm = this
                if (!vm.isStart) {
                    vm.countVal = vm.countVal ? vm.countVal : new Date().getTime()
                    var timer = setInterval(function() {
                        vm.counterFn(vm.countVal)
                    }, 10)
                    vm.globalTimer = timer
                    vm.isStart = true
                }
            },
            stopCountFn: function() {
                var vm = this
                if (vm.isStart) {
                    window.clearInterval(vm.globalTimer)
                    vm.globalTimer = null;
                    vm.isStart = false
                    vm.pauseTime = new Date().getTime()
                }
            },
            passToParent: function(data) {
                var vm = this
                this.$emit("getDataFromChild", data)
            },
        }
    }
</script>

<style scoped>

</style>
